Wednesday, April 13, 2016

Dams On Susquehanna Are Undoing Progress In Reducing Pollution To Chesapeake Bay

The head of the U.S. Geologic Survey’s Chesapeake Bay Water Quality Monitoring Program Tuesday said water quality is improving in the Pennsylvania portion of the Bay watershed because of the steps being taken to reduce pollution, but some of the progress is being undone, particularly in sediment and phosphorous loadings, because the reservoirs behind three dams in the lower Susquehanna are about filled with sediment.

Scott Phillips, Chesapeake Bay Coordinator for the USGS, provided the Senate Environmental Resources and Energy and Agriculture and Rural Affairs Committee members with an overview of the water quality improvements from monitoring stations in the Pennsylvania part of the Susquehanna Watershed and throughout the Bay drainage area.

Phillips said of 18 monitoring sites looking at nitrogen in Pennsylvania, 14 show improvement and 4 show degrading conditions or no change. The range of results shows from one to almost 33 pounds per acre across the watershed, with an average in Pennsylvania of 11.5 pounds per acre. The highest loads are in the lower part of the Susquehanna Watershed.

He said the results clearly show the combination of measures being taken in Pennsylvania are working to reduce nitrogen pollution.

With respect to total nitrogen loads going into the Chesapeake Bay itself from the Susquehanna River, loads have declined from 1985 to present day generally, but have generally plateaued at a lower level.

With respect to phosphorous levels, Phillips said Pennsylvania and the Chesapeake watershed are similarly seeing improvements, though the results are still showing above average loads per acre.

Sixty-eight percent of stations are showing improvement in phosphorous, 20 percent degrading and 12 percent no trend. Again, the measures being taken are working, said Phillips.

With respect to total phosphorus going into the Chesapeake Bay itself, the trend was downward from 1985 to 1995, but then it steadily increases until present day. The primary reason being the reduced effectiveness of the Holtwood, Safe Harbor and Conowingo (photo, USGS) dams in the lower Susquehanna in trapping sediment and its embedded phosphorous.

Phillips noted the measures taken from Marietta, Lancaster County up the Susquehanna have reduced phosphorus. It’s the results in the Lower Susquehanna, after the dams, which increased.

Phillips said the results, particularly below the Conowingo Dam just south of the Pennsylvania-Maryland border, show less improvement because this dam in particular is at capacity in trapping sediment.

Phillips said the water quality results lead to three conclusions: what works in reducing pollution are upgrades to wastewater treatment plants, reductions in air emissions, and installation of agricultural best practices.

The challenges include the time it takes between installing best management practices and when they become fully effective, runoff pollution from development, and intensified agriculture overwhelming best practices.

Phillips said the results point to an opportunity to target nutrient and sediment reduction efforts, and improving stormwater management and monitoring. After the presentation, Phillips said, “The item that needs more emphasis in the story is that while the majority of trends in Pennsylvania are improving, the levels of nitrogen and phosphorus are still high compared to the rest of the Chesapeake watershed. Therefore, more actions will be needed to meet reduction targets to improve water quality in the Bay.”

Sen. Gene Yaw (R-Lycoming), Majority Chair of the Senate Environmental Committee, said it appears targeting implementation requirements in areas where the loadings are highest, rather than having the same requirements over the entire watershed, may be a better use of resources.

Sen. Yaw also said the results showing the impact the three dams have in declining sediment and phosphorous results is a concern.

Phillips suggested the U.S. Army Corps of Engineers has developed some options, including more practices upstream to reduce the phosphorous coming into the reservoirs. He indicated dredging was determined to be less feasible.

He added a multi-state approach will likely be needed to deal with the reservoirs.

Sen. Judy Schwank (D-Berks), Minority Chair of the Senate Agriculture Committee, noted farmers and others will have to maintain the practices they installed to keep them as effective as possible.

The U.S.G.S. information is a snapshot of where Pennsylvania is in terms of nutrient and sediment pollution, but was no information on how far Pennsylvania has to go yet.

For more on Chesapeake Bay-related issues in Pennsylvania, visit the CBF-PA webpage. Click Here to sign up for Pennsylvania updates (bottom of left column). Click Here for a copy of CBF-PA’s most recent newsletter.

Click Here to watch a video of the information hearing. Click Here for a copy of the PowerPoint presentation. Click Here for a summary of the presentation.

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About Me

This Blog is a companion to www.PaEnvironmentDigest.com, the weekly online newsletter published by Crisci Associates, Harrisburg, PA.
I can be contacted at 717-576-0420 or by sending email to: DHess@CrisciAssociates.com.
I served as Secretary of the Pennsylvania Department of Environmental Protection from 2001 to 2003, Executive Deputy at DEP from 1995 to 2001, as staff to the PA Senate Environmental Committee and various positions in the former Department of Environmental Resources, working on environmental issues for nearly 40 years.